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  • Need help with blending preservatives and boosters

    Posted by chaseerin7 on August 30, 2021 at 11:33 pm

    Hello, I have started formulating skincare products on a small scale.  At this point, I only have the ability to purchase from redistributors like Formulators Sample Shop, Lotion Crafter, Making Cosmetics etc.  I have been trying a lot of different preservatives but would like to simplify my ingredient stock.

    I am looking for guidance/resources on formaldehyde-free preservatives for products for sensitive skin…mainly o/w lotions & serums.  Most products are <5.5pH but I do have some formulas with Niacinamide w/pH around 6.1

    I always use a chelator (typically Sodium Phytate / Dermofeel PA-3) and airless or UV protected containers.  I also tend to use Propanediol instead of Glycerin, is this helping as an additional booster?  

    I have had good results with Euxyl PE 9010-but should I be adding additional boosters? i.e sodium benzoate or GMCY if working with plant-based extracts?Or should I be blending the PE9010 with another “broad spectrum” preservative blend? If so, how do I figure out the correct ratio/% of each preservative when mixing/blending in a formula?

    I would like to move away from Phenoxyethanol but do not like the odor of benzyl alcohol. Any recommendations for preservatives that do not have a strong odor (i.e Geoguard ECT and Euxyl K903). I have had good results with Linatural Ultra 3, but I am struggling to meet the MQO at this stage.

    Thank you very much for your time and knowledge…I have been trying for a while to find information to answer these questions without luck!

    Microformulation replied 1 year, 3 months ago 7 Members · 9 Replies
  • 9 Replies
  • PhilGeis

    Member
    August 31, 2021 at 1:28 pm

    Right - use (e.g.) benzoate with Euxyl PE 9010.  “Broad spectrum” is largely marketing so be cautious when you see it.

    Phytate/Euxyl K903 is ok, esp. in surfactant products.  Geogard ECT not so much and do not use Linatural  3.  - PEA partitioning is an issue, esp. in smaller packages and with implements (e.g. mascara brushes).
    Whatever you use, make sure you show efficacy in final packaged stability. 

    Propanediol vs Glycerine is nothing to count on.

  • chaseerin7

    Member
    August 31, 2021 at 1:53 pm

    @PhilGeis Thank you!
    re: Euxyl PE 9010,  use at 1% and add benzoate at .25 or.5%?  This is where I struggle… what % of the additional preservative is needed? Is there another recommended “booster” preservative that is better for sensitive skin? 

  • Abdullah

    Member
    August 31, 2021 at 2:35 pm

    If your emulsifier support it drop the pH to below 5. It will help your preservative a lot and is better for your skin too. 

    You don’t need pH above 6 for niacinamide. It works fine at pH 5 and below. 

    Why you want to move away from phenoxyethanol? It is one of the top preservatives in terms of effectiveness and mildness. 

  • PhilGeis

    Member
    August 31, 2021 at 4:38 pm

    Phenoxyethanol at 0.5% and Na benzoate at 0.26%.

    Amen to my colleague Abdullah’s comment!

  • chaseerin7

    Member
    August 31, 2021 at 4:56 pm

    Thank you @Abdullah and @PhilGeis

    I will stay with phenoxyethanol, and continue to educate my customers, as it is safe and it works! 

    I would love to keep my product at a pH ~5. I was worried about references to Niacinamide products below pH 6 causing hydrolysis and formation of nicotinic acid???

  • Emotelle

    Member
    October 28, 2021 at 9:28 am

    I think when customers see the word “phenoxyethanol”, they freak out thinking it is some alcohol that will harm their sensitive skin.

    So what pairs well with Euxyl PE9010 to boosts its preservation effectiveness? Do you all have something to recommend?

  • PhilGeis

    Member
    October 28, 2021 at 11:20 am

    Emotelle said:

    So what pairs well with Euxyl PE9010 to boosts its preservation effectiveness? Do you all have something to recommend?

    What’s the product?

  • DesertInBloomCosmeticsLab

    Member
    October 28, 2021 at 1:55 pm

    @chaseerin7:

    Drop your pH to 4.8 … in a cosmetic product it is very rare that you need to worry about a chemical reaction due to pH levels.  Niacinamide actually works best in the pH range 4.5 to 5.0.

    Phenoxyethanol … nothing wrong with it as a preservative, but check with your retail channel partners … retailers are increasingly putting phenoxyethanol on the No list.

    Linatural Ultra-3 … you can make your own blend by purchasing the 3 components separately.

  • Microformulation

    Member
    October 28, 2021 at 1:58 pm

    Emotelle said:

    I think when customers see the word “phenoxyethanol”, they freak out thinking it is some alcohol that will harm their sensitive skin.

    Not in my experience. Any push back I have seen was from distributors who felt it wasn’t natural. That is based on 100’s of Formulas with PE9010.

  • Graillotion

    Member
    October 28, 2021 at 5:33 pm

    I will repeat what has been said….take you niacinamide formulas down to 4.8.  When you finally dig out the one piece of misinformation on my why re-packers say that…it will make you sick.

    If you play around with the search bar….you can find it here.  Trust the info you get here…1000 times more than the re-packers.